One worker was hospitalized in critical condition and three others fell ill after a carbon dioxide leak that led to a brief evacuation Monday morning at LAX Terminal 8.
A hazardous materials team from the Los Angeles Fire Department responded to the baggage claim area of that terminal around 7 a.m. to provide assistance.
Passengers were cleared from the area, a spokesperson for LAX said in an emailed statement.
"There is an initial report of a gas leak in the terminal and at least some of the area has been cleared of passengers for the investigation," the statement said. "We are gathering more information."
Get top local stories in Southern California delivered to you every morning. >Sign up for NBC LA's News Headlines newsletter.
According to the LAFD, the carbon dioxide leak took place inside a utility room. LAFD Public Information Officer Captain Erik Scott said during a 10 a.m. press conference that the carbon dioxide came from the fire extinguishing system in that room, which is an electrical equipment room.
To avoid damaging the electrical equipment in the room, instead of a sprinkler system, when there's a chance of fire, the fire extinguishing system releases a "deluge" of carbon dioxide. That odorless, colorless gas displaces all of the oxygen in the room, starving any fire that might be present.
LAFD officials said they are still investigating why the carbon dioxide was released, but said there was no explosion and no electrocution.
Local
Get Los Angeles's latest local news on crime, entertainment, weather, schools, COVID, cost of living and more. Here's your go-to source for today's LA news.
The four individuals who became sick were all employees either in the room or nearby "when a popping sound was heard, and the apparent release of Carbon Dioxide vapor took place."
Two men and one woman were treated for "minor complaints." The fourth person, a man in his 50s, was found in the utility room, not breathing and without a pulse.
According to Scott, the man suffered cardiac arrest when the carbon dioxide replaced the oxygen in the room.
LAFD paramedics issued CPR and rushed the man to the hospital, where he is now in critical condition -- an improvement from grave condition.
According to Scott, the man was breathing and his blood was pumping on his own when he was transported.
NewsChopper4 was over the scene around 8 a.m. on Monday.
As many as 100 passengers were sent to Terminal 7 after being evacuated from Terminal 8 while the LAFD crew investigated.
There was no danger to the passengers near the baggage claim area in the terminal, which was at least 200 feet away from the electrical room.
The electrical room is subterranean, Scott said, and carbon dioxide is heavier than air, so all the gas would have sunk rather than rising and creating a danger to the other passengers.
After carefully testing the area with instruments, only trace amounts of carbon dioxide were detected in the utility room.
Portable fans were set up by the hazmat crew to ventilate Terminal 8 with outside air.
The situation was "under control" by the 10 a.m. press conference, Scott said, and the reason Terminal 8 remained closed was so the fire department could ensure the system that releases the carbon dioxide is working correctly.
Some flights were delayed by the closure of Terminal 8, as planes that would have arrived at that terminal were told to stay in their originating airports, LAX told NBC4.
Terminal 8 and Terminal 7 are connected, so all passengers that had to evacuate were able to do so with minimal impact and without leaving the building.
